Interest in sensors and actuators and the availability of new fabrication approaches is leading to growing interest in micro- and nano-electromechanical systems (NEMS), oscillators, and resonant systems. One of the possible applications of NEMS resonant devices is sensitive detection of bound mass. Most earlier work has been devoted to the immobilization of target species onto the surface of the resonating structure. In such a scenario, pathogen-binding events alter the mechanical stress of the oscillator and its total mass and thus influence both the bending and the natural frequency of the cantilever. Signal transduction is generally achieved by employing an optical deflection (or interferometric) system to measure the mechanical bending or the frequency spectra resulting from additional loading by the adsorbed mass. Such systems generally do not achieve sufficient sensitivity to mass changes to reliably detect very small bound masses.